The California Fish Passage Forum is a consortium of state and federal agencies and NGO’s whose mandate is to improve fish passage in anadromous waters. The Forum is now embarking on the implementation of a state wide methodology for prioritizing the removal of artificial fish passage barriers. The methodology, which employs sophisticated optimization modeling and solution techniques, represents a radical improvement over standard, scoring-and-ranking type procedures commonly used for prioritizing barriers in the US, Canada and other parts of the world. Optimization based methods provide a systematic and objective means of targeting barrier mitigation decisions which maximize restoration gains given available resources. The optimization methodology being implemented by the Forum integrates information on barrier location, passability and cost together with river habitat and quality data for multiple target species in order to identify cost-efficient passage improvement strategies. Critically, the spatial structure of barriers and the interactive effects of passage improvement on longitudinal connectivity are explicitly taken into consideration. Another key feature of the Forum’s prioritization methodology is its ease of use. A user-friendly program called APASS (Anadromous Fish Passage Optimization Tool), replete with a graphical user interface, has been implemented, allowing Forum members to quickly and easily generate optimized solutions. Additional functionalities have been built into APASS for performing batch runs across a range of budget values and for performing basic what-if analyses such as varying the weights placed on different target species, changing the spatial focus (i.e., selecting subsets of watersheds) and forcing specific barriers in or out of the final optimal solution. Besides its use as a strategic planning tool for targeting high impact barriers across the state, APASS can also be used for screening among projects that have been submitted to the Forum for possible funding. APASS has been purposely designed as a generic planning tool that can be applied to any geographic area. It is available free for academic and non-commercial use.